As drilling operations for natural gas and oil in the U.S. have expanded into shale and other unconventional underground formations, so has the list of public health threats associated with hydraulic fracturing, a drilling technology developed to extract these resources.
One particularly ominous threat to human health is silica, a type of sand frequently used to prop open underground fractures that release trapped oil and gas. Exposure to airborne silica can cause lung cancer and silicosis, an incurable lung disease.
Last summer, the federal Occupational Safety and Health Administration issued a hazard alert to workers at hydraulic fracturing sites to warn them about the dangers of breathing silica dust. The agency said that 79 percent of the air samples its safety experts had collected at drilling sites in five states demonstrated silica exposure greater than the recommended safety limit. Since hydraulic fracturing sites can be located within a few hundred feet of schools and homes, residents of communities experiencing rapid oil and gas development can be exposed to these dangerous particles.
Residents living near silica sand mines in states such as Wisconsin and Minnesota have begun to voice concerns about the health effects of silica exposure. The Minnesota Pollution Control Agency has acknowledged that health risks exist but says that “[t]here are no federal or state standards for silica in ambient air.”
The bottom line? Like many other issues associated with hydraulic fracturing, the public health risks posed by frac sand are not fully understood. Before American communities rush forward with more drilling, they must demand substantial research to determine whether this type of energy production can be conducted in a way that does not pose potentially devastating consequences.
